1. Field of the Invention
The present invention relates to an electrical connector assembly, and particularly to a stacked modular jack assembly for LAN (Local Area Network) application and having improved magnetic module for reducing and suppressing noise.
2. Description of Related Art
It is quite common to use modular jacks for the data transmission in high speed applications such as IEEE 802.3 10Base-T or 100Base-T local area networks. A common problem to these high speed modular jacks is their tendency to emit high frequency radiation. There is also a need to provide means for suppressing undesirable noise.
Noise suppressors or signal conditioning components, such as common mode choke coils, are known in the art. The noise suppressors are mounted on a mother board on which the modular jack is seated. The noise suppressors are electrically connected with the modular jack by wires on the mother board. However, such signal conditioning components consume board space, which could otherwise be used for other circuitry. Furthermore, since the signal conditioning components are distant from the modular jack, the signal traces required to route the signals from the modular jack to the signal conditioning components degrade the signal integrity somewhat, thereby lowering the signal-to-noise ratio.
U.S. Pat. No. 5,069,641, issued to Sakanmoto et al on Dec. 3, 1991, discloses a modular jack assembly comprising a dielectric housing and a printed circuit board (PCB) disposed within the housing. The PCB contains noise suppressors. A common mode choke coil and a three-terminal capacitor arrangement are used as a typical noise suppressor. The PCB is fitted with contactors and terminals respectively for contacting with a modular plug and mounting the modular jack assembly on a mother board. The contactors and the terminals are electrically connected with the noise suppressors by wires on the PCB. For saving space, the PCB is disposed perpendicularly to a bottom surface of the housing, while such arrangement is unstable.
U.S. Pat. Nos. 5,587,884 and 5,647,767, respectively issued to Raman on Dec. 24, 1996 and Scheer et al. on Jul. 15, 1997, and both assigned to The Whitaker Corporation, each disclose a modular jack assembly comprising an insulating housing and an insert subassembly received in the housing. The insert subassembly includes front and rear insert members. The front insert member has contact terminals encapsulated therein for mating with a modular plug. The rear insert member has a printed circuit board and leads encapsulated therein. The printed circuit board contains signal conditioning components such as common mode choke coils. The leads extend downwardly for electrically connecting to external circuits, such as a mother board. The terminals and the leads are soldered to the printed circuit board and electrically connected with the signal conditioning components by wires on the printed circuit board. Since the noise induced in the contact terminals of the modular jack assembly have similar spectral content, adequate cancellation of noise can be achieved by differential circuits. However, high speed applications such as 100 mbps local area networks require additional more sophisticated signal conditioning circuitry.
U.S. Pat. No. 5,687,233, issued to Loudermilk et al on Nov. 11, 1997, assigned to Maxconn Incorporated, discloses a modular jack assembly addressing the problem encountered in the ""884 and ""767 patents. The modular jack assembly employs a number of signal conditioning components such as capacitors and magnetic coils to provide sufficient conditioning of data transmission. Signal pins are divided into a contact pin array and a mounting pin array. The two pin arrays are electrically coupled through an internal printed circuit board which has the capacitors and magnetic coils thereon. However, because the capacitors and magnetic coils are all mounted on the same printed circuit board, mutual interference between the signal conditioning components may also be a problem.
Recently, in order to save valuable real estate of mother boards in electronic devices, modular jacks are developed to be arranged in a stacked manner. Setwart, headquartered in Glen Rock, Pa., posted an article, entitled xe2x80x9cMagJack Family of Modular Jacks with Integrated Magneticsxe2x80x9d on the Internet website address, http://www.stewartconnector.com/pdfs/magjkfy.pdf. A modular jack introduced in this article has upper and lower ports. Two magnetic components needed for the upper and lower ports are housed within a jack body for protecting signals from internally and externally generated noise. However, because the two magnetic components are directly mounted in the jack body, crosstalk or EMI (Electromagnetic Interference) between the two magnetic components may become a serious problem.
Hence, a stacked jack assembly having improved magnetic module is required to overcome the disadvantages of the prior art.
It is an object of the present invention to provide an electrical connector assembly having improved magnetic module for providing sufficient electrical function.
It is another object of the present invention to provide a stacked modular jack assembly having improved magnetic module for easy assembly.
In order to achieve the objects set forth, an electrical connector assembly in accordance with the present invention comprises an insulating housing and an electrical subassembly disposed within the housing. The electrical subassembly includes first and second contact array assemblies, a pair of magnetic modules each having a container for retaining a plurality of magnetic coils therein, a plurality of upper and lower pins respectively disposed on upper and lower portions of the container and being coupled to the magnetic coils, some of the upper pins are electrically connected to the corresponding contact array assembly, and the lower pins are electrically connected to a mother board.
Other objects, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.